Underground antenna



Dec. 22, 1931.

L. KLEIN UNDERGROUNDANTENNA Filed Feb. 28, 1929 2 Sheets-Sheet 1 De. 22, 1931. 1 KLEIN UNDERGROUND ANTENNA Filed Feb. 28, 1929 2 Sheets-Sheet 2 f gfx/vendez lea'w,

.Zea 7 Patented Dec. 22, 1931 A UNrrED 'rares lPATENT ori-ica LED KLEIN, OF DETROIT, MICHIGAN UNDERGROUND ANTENNA Application led February 2S, 1929. Serial No. 343,383.

The present invention relates broadly t Figure 2 is an enlarged side elevation of improvements in radio apparatus and more the underground antenna per se, a portion particularly to an antenna that is adapted o f the asphalt covering being broken away to to be buried beneath the earth. show the convolutionsof the outer coil that @ne of the primary objects of the present surrounds the cylindrical casing. 55 invention is to provide an underground an- Figure 3 is a top plan view of the under-V tenna which aims to eliminate static and atground antenna. mospheric disturbances whereby to increase Figure 4 is a vertical sectional view through the efficiency in the operation of the radio rethe cylindrical casing and the outer coil ceiving apparatus with which the undershowing the inner coil in elevation; and 6G ground antenna is adapted to be associated. Figure 5 is a transverse section taken ap- Another important obj ect of the invention proximately on the line 5-5 of Figure 4 lookis to provide an underground antenna that ing downwardly. includes concentrically arranged energy col-- In thedrawings wherein for the purpose lecting coils of insulated wire, the ends of of illustration is shown the preferred em- 65 said concentric coils being connected together, bodiinent of my invention, the numeral 1 desboth energy collecting coils being buried beignates generally my improved underground neath the ground with a lead wire extending antenna, the saine comprising a drum or casfrom the inner coil upwardly out of the ing including a cylindrical body 2, preferground for connection to the radio receiving ably constructed of sheet copper. Suitable 70 set. closure caps 3 are secured within the respec- A still further object of the invention is tive ends of the casing 2 and the caps may to provide an underground antenna of the be soldered in an air-tight manner subseabove-mentioned character wherein the inquent to the positioning of the inner coil 4 ner coil is confined within a cylindrical caswithin the casing. This inner coil 4 is spaced ing, the outer coil being disposed around from the inner wall of the cylindricalrcasthe outer peripheral face of the casing so that ing and extends for substantially the full said coils are maintained in spaced r-elation length thereof. The inner coil 4 is preferably with respect to each other, there being an asformed of fourteen gage copper wire.

phalt covering` or coating over the convolu- A similar coil 5 has its convolutions encir- 80 tions of the outer coil for protective purposes, cling the casing 2 for substantially the entire and further for the purpose of maintaining length thereof and these coils are covered the convolutions of the outer coil in spaced with suitable insulation and it will be further relation. observed that the convolutions of each of the 25 Another object of the invention is to pron coils are spaced with respect to each other. S5k vide an underground antenna which is siin- For the purposeof further maintaining ple in construction, inexpensive, strong andl the convolutions of the outer coil in spaced durable and further well adapted for the purrelation with each other and to further prooses for which it is designed. tect the outer coil, the outer surface of the Other objects and advantages of the incasing and its closure capsV as Vwell as the 90 vention will become apparent from the folinsulated wire 5 are coated with asphalt and lowing description when taken in connection this asphalt covering is indicated at 6. with the accompanying drawings: The lower end of the inner coil 4 extends 1 In the drawings wherein like reference through the side of the casing 2 adjacent the j l characters indicate corresponding parts bottom thereof and is soldered to the ad- 95 throughout the saine; jacent end of the outer coil 5. In a similar Figure 1 is a side elevation of the undermanner, the upper end of the inner coil 4 eX- ground antenna embodying my invention tends through an opening provided therefor showing the same buried beneath th-e earth in the side of the casing 2 and is soldered to and being connected to a radio receiving set. the adjacent end of the outer coil. In this l0@ manner, the energy collecting coils are operatively connected together.

A lead wire 7 that is covered With suitable insulating material is connected at its lower end to the upper end of the inner coil 4 and this lead wire extends upwardly through the upper cap 3, the upper end of this lead wire having communication or connection With the radio receiving set A in the conven-l K tional manner. In Figure l of the drawings, there is illustrated diagraminatically the manner in which the underground antenna embodying my invention is buried beneath the earth and how the lead wire 7 extends upwardly through the earth for connection at its upper end with the radio receiving set. A ground wire 8 has connection at one end with the usual ground terminal on the radio receiving set while the ground plate that is embedded in the earth has connection with the otherA end of the ground wire 8 and this ground plate is shown at 9.

The provision of an underground antenna of the above-mentioned character will enable the radio receiving set to operate more efficiently than with the use of overhead antennas, and furthermore, due to its simplicity, the present antenna can be constructed at a Very low cost. Also by coating the casing and the outer coil with asphalt in the inanner as shown and described, the earth will not force together the convolutions of the outer coil and also said asphalt covering will act as a protective medium againstthe elements.

- Vhile I have shownA a preferred embodi ment of my invention, it is to be understood that minor changes in the size, shape and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the appended claim.

What is claimed is:

In an underground antenna, a casing adapt ed to be buried beneath the earth, an energy collecting coil arranged Within the casing, a second energy collecting coil encircling the casing, said coils being connected together at their respectiveends, and a lead wire extending upwardly from one of the coils through the top of the casing above the earth for connection with a radio receiving set, and an asphalt coating over the casing and the outer coil, said coating maintaining the convolutions ofl the outercoil in spaced relation with respect to each other.

In testimony whereof I affix my signature.

LEO KLEIN. 

